6beta, 19-oxido pregnanes



United States Patent 3,008,957 6 3,19-0XIDO PREGNANES Howard J. Ringold and Albert Bowers, Mexico City, Mexico, assiguors to Syntex S.A., Mexico City, Mexico, a corporation of Mexico No Drawing. Filed July 29, 1960, Ser. No. 46,077 Claims priority, application Mexico Jan. 6, 1960 21 Claims. (Cl. 260-23955) The present invention relates to novel cyclopentanophenanthrene compounds and to a process for the preparation thereof.

More particularly, the present invention relates to novel 63,19-oxido and lactones of the pregnane series having a keto or a hydroxyl group at G3, a keto group at C-20 and which may also contain a hydroxy or acyloxy group at 0-170; and unsaturation at 0-1.,2 and 04,5.

The novel compounds of the present invention which are progestational agents having anti-androgenic, antiestrogenic and anti-'gonodotropic activities as well as being bacteriostatic against gram positive and gram ne gative bacteria, are represented by the following formulas:

3,008,957 Patented Nov. 14, 1961 In the above formulas, Y represents keto, B-hydroxy or fi-acyloxy; X represents fihydrorry or fi-acyloxy and R represents hydrogen, hydroxy or acyloxy. When Y is keto in compounds of Formula -A, unsaturation may be present at C-l,2 and C4,5.

The acyl groups are derived from hydrocarbon carboxylic acids containing up to 12 carbon atoms, saturated or unsaturated, of straight, branched, cyclic or cyclicaliphatic chain, aromatic and may be substituted by functional groups such as hydroxyl, acy-loxy 01? up to 12 carbon atoms, alkoxy of up to 8 carbon atoms, amino or halogen. Typical ester groups include the acetate, propionate, butyrate, hemisuccinate, enanthate, caproate, benzoate, phenoxyacetate, trimethylacetate, arninoacetate, cyclopentylpropionate and ,B-chloropropionate.

The novel compounds of the present invention are also cardiac anti-fibrillatory agents, lower the blood cholesterol and are useful in thetreatrnent of pre-rnenstrual tension.

The novel compounds of the present invention are prepared by a method illustrated 'by the following equation:

In the above equation, Ac represents acetyl; however, other acyl groups derived from hydrocarbon carboxylic acids containing up to 12 carbon atoms of the type previously described may be employed.

In practicing the process outlined above, the starting material Gfl-hydroxy-tigogenin acetate is prepared by converting diosgenin acetate into the Soc-*bIOHlO-Gfi-hYdIOXY derivative by reaction with hypobromous acid or a systern which generates hypobromous acid such as N-bromoacetamide and perchloric acid. Upon subsequent treatment with 8 N chromic acid, the (SB-hydroxy group is oxidized to' the keto group and the Sa-bromo group is then removed by reductive debromination as by treatment with zinc. in acetic acid to thus form 6-keto-tigo genin acetate. Upon hydrogenation of the latter compound in mixture of acetic acid and ethanol and in the presence of a catalyst such as platinum oxide the keto group is reduced to the hydroxyl group and there is formed 6,8-hydroxy-tigogenin acetate (I). Alternatively the reduction may be carried out with lithium aluminum tri-tertiary butoxyhydride.

The latter compound (I) is refluxed for about five hours with lead tetraacetate, preferably in a solvent such as benzene, to form 65,19-oxido-tigogenin acetate (II). Degradation of the side chain is then efiected by conventional methods such as heating the sapogenin (II) with acetic anhydride in a closed vessel, tollowed by hydrolysis of the excess of acetic anhydride, orn'd-ation with chromic trioxide in acetic acid, and cleavage of the acid residue at -16 by refluxing with a mixture oi 70 potassium hydroxide and acetone to thus produce 613,19- oxido-A -pregnen-3/3-ol-20-one, which is reesterified at (3-3 by conventional esteriiication methods to finally produce 3fi-acyloxy- 6,8,19-oxido-A -pregnen-20-one (III), preferably the B-acetate thereof.

For formation of the novel compounds of the present invention containing a hydroxy or acyloxy group at 0170:, the 3fi-acyloxy-6fl,19-oxido-A -pregnen-20-one (III) is reacted with aqueous alkaline hydrogen peroxide to form the 16a,17a-oxide (IV) with simultaneous sapon-ification of the ester group. The latter compound is then reacted with hydrogen bromide in glacial acetic acid to open the 16m,17a-epoxide ring to produce 65,19-oxido-16fibromo-pregnane-3fi,l7u-diol-20 one which is then transformed into the 65,19-oxido-pregnan-3B,17a-diol-20'one (V) by removal of the 16B-bromo group by reductive debrornination as by treatment with hydrogen in the presence of a catalyst such as Raney nickel or palladium on calcium carbonate. Esterification by conventional methods with hydrocarbon carboxylic acid anhydrides or chlorides containing less than 12 carbon atoms affords the 3-monoesters (Va). Esterification of the C-l'Ya-hY- droxyl group may then be effected with the same or different hydrocarbon carboxylic acid anhydride in benzene solution and in the presence of p-toluenesul-fonic acid to thus afford the 3,17-diesters having the same or different ester groups (Vb). The diesters having the same ester groups may also be prepared in one step by employing the latter method of esterification of the free 36,170:- diol with the desired acid anhydride.

Upon treatment of the 6/3,19-oxido-pregnane-3fi,17adiol-ZO-one (V) with chromic acid in acetone the 33- hydroxyl group is converted into the 3-keto group and there is thus formed the 613,19-oxido pregnan-l7a-ol-3,20- dione (VI) which upon esterification in the manner described above with hydrocarbon carboxylic acid anhydrides in benzene solution and in the presence of p toluenesulfonic acid is converted into the 17u-ester derivatives (VIa). Upon dehydrogenation of the latter compound as by heating with 2,3-dichloro-5,6-dicyano-1,4-

benzoquinone, there is obtained .6B,19-oxido-A t -pregnadien-17a-o1-3 ,'20adione acylate ('VIIa).

For formation of the novel compounds of the present invention lacking -a hydroxyl or aoyloxy group at C-17a, the Sfi-aoyloxy-(SB,l9-oxido-A -pregnen-20-one (III) is hydrogenated in methanol in the presence of a catalyst such palladiumon carbon to thus produce 3,8-acyloxy- .6 fl, l9-ox ido-pregnan-20-one (VIHa) which upon hydrolysis as by treatment with dilute methanolic potassium hydroxide is converted into the free alcohol 6B,-19-oxidopregnan-3Bol-20-one (VIII). Alternatively, the latter compound is produced by the hydrogenation in the same manner of 6B,l9-oxide-A -pregnen-3 3-ol-20-one formed by the saponification of compound H1. The 6p,19- oxidopregnan-Sfi-oi-QO-one 1 is then oxidized with '8 -N .chromic acid in acetone in form the 6fl,19- oxido pregnanc- 3;20+dione (IX) which can then be dehydrogenated as by refluxing with 2, 3-dichloro-5,6-dicyan0 l,4-benzoquinone in asolvent such as dioxane for a period of time in the order of 18 hours to finally produce 65,19-oxido- A -pregnadiene-3,20-dine (X).

The formation .of the novel lactones of the present in- -vention can be illustrated by the following equation:

I ---0R l? i CH3 6:0 '---0R 0 i. ii

R".O' i\ XIV i CH: ':=o on IQ t I R i on, i'1=o (i=0 |---'OR xvi In the above equations R and R" represent the acyl radical of hydrocarbon carboxylic acids of the type described hereinabove.

In practicing the above invention, the 6;8,19-oxidopregnan-3fi-ol-20-0ne acylate (VHIa) or 65119' Xid0-P1'6gnan-35,17a-diol-20-one diacylate (Vb) is oxidized with chrornic acid in aqueous acetic acid to form the corresponding 6,19-lactone, more specifically, the 6,19-lactone of 3B-acyloxy-GB-hydroxy-20-keto-pregnane-19-carboxylic acid (XI) or the 6,19-lactone of 6,8-hydroxy-20-keto-3/3, -17a-diacyloxy-pregnane-19-carboxylic acid (XIV). By tretament of the aforesaid 6,19-lactone with dilute methanolic potassium hydroxide, there is formed the 6,19-lactone of 3fi,6,8 dihydroxy-ZO-keto-pregnane-19-carboxylic acid (XII) or the 6,191actone of 3B,6;8-dihydroxy-17uacyloxy-20keto-preguane-19-carboxylic acid (XV), which can then be oxidized with chromic acid to the corresponding 3-keto-oompounds (XIII) and (XVI) respectively.

The following examples serve to illustrate but are not intended to limit the scope of the present invention:

Example I 5 1g. of diosgenin acetate was suspended in 50 cc. of dioxane and treated with 6 cc. of 0.46 N perchloric acid and then with 2 g. of N-bromoacetamide, the latter was added little by little, with stirring during the course of an hour, in the dark and maintaining the temperature at about 15 C. The mixture was stirred for 1 hour further in the dark at room temperature and then decolorized by the addition of 10% aqueous sodium bisulfite solution; 1 liter of water was added and the product was extracted with methylene chloride. The extract was washed with water, dried over anhydrous sodium sulphate and the solvent was evaporated under reduced pressure and at temperature. The residue consisted of the 3- acetate of 5a-bromo-6fi-hydroxy-tigogenin.

There was prepared 50 cc. of an 8 N solution of chrornic acidfrom 13.4 g. of chromium trioxide, 12.5 cc. of concentrated sulfuric acid and distilled water. A solution of 5 g. of the 3-acetate of 5u-bromo-Gfl-hydroxytigogenin in 50 cc. of acetone was cooled to 0 C., flushed with nitrogen and treated with the 8 N solution of chromic acid until the characteristic color of chromium trioxide persisted in the mixture. The 8 N chromic acid solution was added in a thin stream under an atmosphere of nitrogen and with stirring at 0 C. The mixture was then stirred at 0 C., under an atmosphere of nitrogenfor two minutes further, poured into ice water and the precipitate formed wascollected by filtration, washed with water, dried under vacuum, thus furnishing the 3-acetate of 5u-bromo-6-ketotigogenin.

The above compound was mixed with 5 g. of zinc dust and 125 cc. of glacial acetic acid, according to the method described in our copending patent application Serial No. 45,790, filed July 28, 1960, and heated at .C. for 1 hour at the end of which it was filtered through celite, the filtrate was concentrated to a small volume under reduced pressure, cooled and diluted with ice water to precipitate the 3-acetate of 6-keto-tigogenin.

The above compound was dissolved in a mixture of 40 cc. of absolute ethanol and 60 cc. of glacial acetic acid and hydrogenated in a Parr instrument at 50 atmospheres in the presence of 0.6 g. of platinum oxide at room temperature for 24 hours, at the end of which the catalyst was removed by filtration and the filtrate was evaporated to dryness under reduced pressure. Chromatography of the residue on neutral alumina gave the pure 3-acetate of 6 3-hydroxy-tigogenin.

To a solution of 2 g. of the 3-acetate of 6B-hydroxytigogenin in 75 cc. of dry benzene was added 3 g. of lead tetraacetate and the mixture was refluxed for 5 hours. It was then cooled, filtered, diluted with water and the ben- ,zene layer was separated, washed with water and the benzene was evaporated under reduced pressure. By chromatography of the residue on neutral alumina there was obperature.

7 tained the S-acetate of 65,19-oxido-tigogenin; M.P. 197- 1990; [od -65.5.

Example 11 A mixture of 1.0 g. of 613,19-oxido-tigogenin acetate and 4 cc. of acetic anhydride was heated in a sealed tube for 2 hours at 195 C. The resulting mixture was cooled, the excess of anhyride was hydrolyzed by adding 100 cc. of water, and allowed to stand for one hour. 500 mg. of chromic trioxide in 12 cc. of acetic acid was then added and the mixture was stirred for three hours at room temperature; it was then diluted with water, extracted with ether and the extract was washed with water, dried over sodium sulphate and the ether was evaporated. The residue was refluxed with a mixture of cc. of 60% aqueous acetone containing 0.5 g. of potassium hydroxide for five hours, the mixture was concentrated to a small volume, cooled, diluted with water and extracted with ether. The extract was washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. By recrystallization from acetone-hexane there was obtained 618,19- oxido-3fi-hydroxy-A -pregnen-20-one.

Reesterification of the 3/3-hydroxy group was effected by conventional reaction with acetic anhydride in pyridine. Thus a mixture of 2.0 g. of 6B,19-0xido-3 3-hydroxy-A pregnen-ZO-one, 10 cc. of pyridine and 10 cc. of acetic anhydride was allowed to remain overnight at room tem- After the usual work-up, there was obtained the 3p acetoxy 6/3,19-0xido-A -pregnen-20-one; M.P. 238-239"; [a] 19; A 240; log 6 4.02.

In a similar conventional manner there was also prepared the propionate, butyrate, cyclopentylpropionate and benzoate.

Example III A solution of 0.07 mol of 65,19-oxido-A -pregnen-3pol-20-one-acetate in 150 parts of methanol was cooled to C. and 5.1 parts of 35% hydrogen peroxide was added. A solution of 0.4 part of sodium hydroxide in 2.5 parts of water was then added with stirring and cooling at such a rate that the temperature did not exceed 25 C. After being allowed to stand at room temperature for 17 hours, the mixture was poured into 400 parts of cold water which was then acidified with dilute hydrochloric acid. The precipitated 16a,-l7a-oxide of 65,19-oxide-pregnan- 3;.3-ol-20-one was collected, washed with water and dried.

Example IV 1 part of the 16a,17oz-0Xid8 of 65,19-oxido-pregnane- 3fi-ol-20-one was dissolved in 25 parts of acetic acid and added, at room temperature with stirring, to a solution of 0.285 part of glacial acetic acid saturated with hydrogen bromide. After half an hour, the mixture was poured into Water, the precipitate was filtered and washed with water until neutral. There was thus obtained 6,9,19-oxido- 1 6,8-bromo-3 fl, l7ot-dihydroxy-pregnan-20-one.

The crude bromohydrin was dissolved in 14.2 parts of ethanol and was stirred overnight with 0.85 part of Raney nickel under an atmosphere of hydrogen. The suspension was filtered through celite, the filter was washed with hot ethanol, the washings and filtrate were combined and then evaporated to dryness. By crystallization from methanol, there was obtained 6,6,19-oxido-pregnan-3fi, 17a-diol-20-one.

1 g. of the above compound Was dissolved in 50 cc. of dry benzene and treated with 2 g. of acetic anhydride in the presence of 200 mg. of p-toluenesulfonic acid and let stand at room temperature overnight. It was then poured into water, the formed precipitate filtered and recrystallized from acetone-ether, thus, affording the diacetate of 6B,19-oxido-pregnane-3B,17ot-diol-20-one.

Example V A solution of 2 g. of 65,19-oxido-pregnan-3fl,l7a-diol- 20-one, obtained as described in the preceding example in cc. of acetone was cooled to 0 C. and treated under an atmosphere of nitrogen under stirring with a solution of 8 N chromic acid until the color of the reagent persisted in the mixture. The oxidizing agent had been prepared by dissolving 26.7 g. of chromium trioxide in 23 cc. of concentrated sulfuric acid and diluting with water to 100 cc.; the mixture was then stirred for 5 minutes more at 0-10, diluted with water and the precipitate was collected, washed with water, dried and recrystallized from ether, thus affording 6,9,19-oxido-pregnan- 17a-ol-3,20-dione.

Example VI 1 g. of 6B,19-oxido-pregnam-17/3-ol-3,20-dione in 50 cc. of dry benzene was treated with 1 g. of acetic anhydride in the presence of 200 mg. of p-toluenesulfonic acid at room temperature and the mixture was allowed to stand for 24 hours. Isolation of the product by extraction with ethyl acetate and crystallization of the residue from acetone-hexane yielded 65,19-oxido-l7oi-acetoxy-pregnane- 3,20-dione. I

By substituting the acetic 'anhydride by other hydrocarbon carboxylic acid anhydrides such as propionic anhydride, butyric anhydride, benzoic acid anhydride, enanthic anhydride, there were produced the corresponding 17a-propionate, 17a-butyrate, 17abenzoate and 17a.- enanthate of 6 8,19-oxido-pregnan-17ot-ol-3,20-dione.

Example V11 T0 1.0 g. of 6/3,19-oxido-pregnan-17a-ol-3,20dione (prepared in Example V) in 50 cc. of dioxane, there was added 3.0 g. of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and the mixture was refluxed for 18 hours. After the usual work-up, there was obtained 6fi,19-oxido-A preg nadien-l7a-ol-3,20-dione.

Example VIII By substituting in the preceding Example the 65,19- oxido-pregnan-17a-ol-3,20-dione by 63,19-oxido-pregnan- 17a-ol-3,20-dione-l7-acetate, there was obtained 613,19- oxido-n -pregnadien-l7a-ol-3,20-dione-17-acetate.

In a similar manner there was obtained the corresponding 6 8-19-oxido l7a-propionoxy-n -pregnadiene- 3,20-dione; 6 3,19-oxido-A -pregnadien 1711-01 3,20-dione-butyrate; 63,19-oxido-A -pregnadien-17a-ol-3,20-dione benzoate and 65,19-oxido-A -pregnadien-17a-ol-3,20- dione enanthate.

Example IX A suspension of 5% palladium on carbon (0.5 part) in methanol (50 parts) was hydrogenated for 30 minutes. A solution of 0.005 mol of 3B-acetoxy-6p,19-oxido-A pregnen-20-one (prepared in ExampleII) in 200 parts of methanol was added to the catalyst and hydrogenated under stirring until one molar equivalent of hydrogen had been absorbed. The solution was filtered and evaporated to dryness; recrystallization of the residue from acetone atforded 3B-acetoxy-6p,19-oxido-pregnan 20-one, M.P. 141-142"; [0:1 +66". I

The above product was dissolved in 100 cc. of 2% methanolic potassium hydroxide and kept'overnight at room temperature. It was then acidified with 2 N hydrochloric acid, heated for half an hour on the steam bath, cooled, diluted with ice water and the product was extracted with several portions of ether. The combined extract was washed with water, dried over anhydrous sodium sulfate and the ether was evaporated. There was thus obtained 6p,l9-oxido-pregnan-3fi-ol-20-one.

scribed in Example II) was hydrogenated by the method described in the preceding example and there was obtained 6B,19-oxido-pregnan 3,Beol-iZO-one, identical with the final product obtained inthe preceding example.

Example XI By following the method described in Example V, 2 g. of 6 3,19-oxido-pregnan-3p ol20-one was oxidized to form 6,3,19-oxido-pregnane-3,20-dione, M.P. 2l4'216; [6!]1 +121 Example XII By following the procedure of Example VII, 65,19- oxid-pregnane-3,ZO-dione was dehydrogenated in the same manner to afford 6 6,19oxido-A -pregnadime-3,20- dione.

Example XIII Example XIV 2.0 g. of the above compound was dissolved in 100 cc, of acetone and treated with 8 N chromic acid in the same manner as described in Example V. After the usual work-up, there was finally afforded the 6,19-lactone of pregnan-6fi-ol-3,20-dione-19-carboxylic acid.

Example XV By substituting in the method of Example XIII the 6,8,19-0xido-pregnan-3fi-0l-20-one acetate by 63,19-oxidopregnan-17a-ol-3,20-dione acetate (cf. Example VI), there was obtained the 6,19-1act0ne of pregnane-6fl,17a-diol- 3,20-dione-19-carboxylic acid-17-acetate.

We claim:-

1. A compound of the following formula:

wherein R is selected from the group consisting of hydrogen and a hydrocarbon carboxylic acyl group containing less than 12 carbon atoms.

2. 6 3,19-oxidc-pregnan-3B-ol-20-one.

3. 6B,19-oxido-pregnan-3fi-ol-20-one acetate.

4. A compound of the following formula:

1.0 wherein Z is selected. from the group consisting gf a double bond betweemC-LZ and C-4,5 and of :a saturated linkage between C''I,;2 and C4,5.

5. 6 3,19-oxido-pregnane-3,20-dione 6. 6fl,I9-Oxido fi 'F' regnadiene-3,ZO-dione. 7. A compound of the following formula e-en Z CH2 Q O J wherein R is selected from the group consisting of hydro; gen and a hydrocarbon carboxylic acyl group containing, less than l2 car-bon atoms and Z is selected from the: group consisting of a double bond between C-1,2 and- 04,5 and of a saturated linkage between C1,2 and C-4,5.

8. 6B,19-oxido-pregnan-17a-ol-3,20-dione.

9. 65,19-oxido-pregnan-17a-ol-3,20dione acetate.

10. 65,19-oxido-A -pregnadien47a-o1-3,20-dione.

11. 6,8,19-oxido-A -pregnadien-17a-ol-3,20-dione acetate.

12. A compound of the following formula:

CHI 6:0 A on,

wherein X is selected from the group consisting of fl-hy; droxy and p-hydrocarbon carboxylic acyloxy containing less than 12 carbon atoms.

14. 618,19-oxido-A -pregnen-3fi-oL20-one acetate.

15. 6 6,19; 16ot,17a-dioxido-pregnane-3B-ol-20-one.

16. A compound of the following formula:

wherein Y is selected 'from the group consisting of keto, fl-hydroxy and fi-hydrocarbon canboxylic acyloxy containing less than 12 carbon atoms.

17. The 6,19-l-actone of pregnane-Bfl,6fl-diol-20-one-19- carboxylic acid.

18. The 6,19-lactone of pregnane -3fl,6fl-diol-20-one-19- carboxylic acid-3-acetate.

19. The 6,19-lactone of pregnan-6p-ol-3,20-dione-19- carboxylic acid.

11 .A compound of the following formula:

wi l 7 R less than 12 carbon atoms. I

21. The 6,19-lactone of pregnane-6,8,17m-diol-3,20- '5 dione-19-carboxy-lic acid-17-acetate.

No references cited. 

1. A COMPOUND OF THE FOLLOWING FORMULA: 